Potato (Solanum tuberosum) is a significant global food crop. Intensive cultivation has heightened dependence on chemical fertilizers, leading to environmental and economic issues. A primary challenge in potato cultivation is the supply of phosphorus, which frequently demonstrates low levels due to leaching, inefficient utilization, and escalating fertilizer manufacturing costs. This study investigates the agronomic and economic benefits of employing natural rock amendments, specifically rock phosphate and feldspar, in conjunction with plant growth-promoting rhizobacteria (PGPR) as a sustainable input instead of chemical fertilizers for enhancing the yield and tuber quality of potatoes. A field experiment was executed to evaluate three treatments: conventional chemical fertilizers (T1), reduced chemical fertilizers combined with PGPR Bacillus megaterium and Azotobacter (T2), and natural rock potassium feldspar, and rock phosphate injected with PGPRs (T3). Regarding tuber quality, T2 and T3 exhibited enhanced tuber quality compared to T1. Also, the highest starch content and the lowest reducing sugar content were in T3. Moreover, T3 demonstrated superior soil quality post-harvest, exhibiting an enhanced total phosphorus level in soil compared to the usual chemical fertilizer treatment, in addition to higher tuber quality. T3 decreased operating expenses by 11% and attained a maximum production of 42 tons per hectare. The return on investment was approximately 79%, accompanied by a 28% profit gain ($3,988/ha) compared to T1 ($2,460/ha). The results show that using PGPR with natural rock fertilizers is a cheaper and effective option compared to regular chemical fertilizers, improving production, profits, and the long-term health of the soil.